Process for breaking petroleum emulsions



Patented Mar. 31, 1942 2,278,168 a FFCE IPRDCESS FOR BREAKING PETROLEUMEMULSIONS Melvin De Groote, University City, and Bernhard Keiser,

Webster Groves, Mo.,

assignors to Petrolite Corporation, Ltd., Wilmington, DeL, a corporationof Delaware No Drawing. Application January 25, 1941, Serial No. 375,978

8 Claims.

This invention relates primarily to the resolution of petroleumemulsions.

One object of our invention is to provide a "novel process'for resolvingpetroleum emulsions of the water-in-oil type, that are commonly referredto as cut oil, roily oil, emulsified oil, etc., and which comprise finedroplets of naturally-occurring waters or brines dispersed in a more orless permanent state throughout the oil which constitutes the continuousphase of the emulsion.

Another object is to provide an economical and rapid process forseparating emulsions which have been prepared under controlledconditions from mineral oil, such as crude petroleum and relatively softwaters or weak brines. Controlled emulsification and subsequentdemulsification under the conditions just mentioned is of significantvalue in removing impurities, particularly inorganic salts, frompipeline oil.

The chemical compound or composition of matter herein described that isemployed as the demulsifier of our process, is a new material,representing a sub-genus of a broad class of sulfation derivatives whichmay be in the form of an ester, a salt, or an acid, but preferably, inone of the two last mentioned forms. If a high molal sulfonic acid beindicated by the conventional formula:

then a hydroxylated ester which may actually have mor than one hydroxylgroup in the radical which replaces the sulfonic acid hydrogen atom, maybe indicated by the following formula:

R.SO3TOH If such ester, for instance, the ester derived from ethyleneglycol, is treated with sulfuric acid, one then can obtain a sulfate ofthe sulionic acid ester, as indicated in the following manner:

The neutralization product derived therefrom by the use of ammoniumhydroxide, for example, may be indicated by the following formula:

A material of the kind above described illustrates the compounds hereincontemplated with certain added provisos:

(a) That the sulfonic acid in the form of a salt or acid besurface-active, as subsequently defined;

(b) That the est-er derived therefrom prior to sulfation, bewater-insoluble; and

(c) That the sulfonic acid be derived from higher fatty acids.

The compounds herein contemplated are derivatives of surface-activesulfonic acids.

By surface-active it is intended to mean that a relatively dilutesolution of alkali metal salts, for instance, the sodium or potassiumsalt and also the ammonium salt, in a solution containing a few tenthsof a percent or thereabouts, will show a marked lowering of the staticsurface tension in comparison with distilled water. Usually, the acidsthemselves show the same surface-active property as the salts.

Although the types of compounds employed as the demulsifier in thepresent process are new chemical products, certain of the raw materialsused in the manufacture of said chemical products, to wit, higher fattysulfonic acids are Well known compositions of matter. However, as theymay be derived in a variety of ways and may show a difference in degree,reference is herein made to suitable means for obtaining higher fattysulfonic acids, particularly adapted as raw materials in the manufactureof compounds of the kind herein contemplated.

It is obvious that the procedure herein described is applicable to themanufacture of various surface-active sulfonic acids, such as fattysulfonic acids, fatty aromatic sulfonic acids, alkylaryl sulfonic acids,and the like. Such broad aspect is contemplated in our co-pendingapplication Serial No. 375,974, filed January 25, 194 1, in which thereis detailed description of a large variety of acceptable types ofsulfonic acids which may be employed as reactants to produce compoundsanalogous to the particular specie or sub-genus herein contemplated.

The present invention relates to a sub-genus of the broad class justdescribed. It is concerned only with sulfonic acids derived from higherfatty acids. The higher fatty acids represent monocarboxy acids havingnot less than eight and not more than 32 carbon atoms. They may besaturated, unsaturated, hydroxylated, non-hydroxylated, etc. They occurcommonly as esters, i. e., glycerides in naturally occurring oils andfats. They are derived from animal or vegetable sources. Common examplesinclude oleic acid, stearic acid, ricinoleic acid, linoleic acid,linolenic acid, etc. Fatty sulfonic acids in the present instance areconcerned with those types in which the sulfonic acid radical isintroduced in the position other than the carboxylic hydrogen atomposition, and is not intended to include the type sometimes referred toas a sulfoaromatic fatty acid, i. e., the type in which the sulfonicgroup is introduced only in an aromatic nucleus. The manufacture of suchfatty sulfonic acids is well known. Such compound may be produced in avariety of ways. Sometimes the procedure results in the formation of thesalt instead of the sulfonic acid itself. In such instances the salt,for instance, the sodium salt, can readily be converted into thecorresponding acid by various procedures. The salt may be dissolved inan alcohol and treated with hydrochloric acid gas so as to hberate thefree sul=y fonic acid along with the precipitation of sodium chloride.The alcoholic solution 'of the sulfonic acid can be separated from theinorganic salt and the alcohol subsequently evaporated. As

illustrating various conventional procedures for the manufacture offatty sulfonic acids of the kind herein contemplated, attention isdirected Farbem'ndustrie Aktiengesellschaft.

Sulfo fatty acids can be converted into bydroxylated esters in variousways. Subsequently, it will be pointed out that the preferred procedureinvolves the use of an alkylene oxide, such as ethylene oxide, butyleneoxide, propylene oxide, or the like. In the use of such last mentionedreactant it becomes obvious that reaction may take place with thecarboxylic hydrogen atom, if present, as well as with the sulfonic acidhydrogen atom. The compounds contemplated in the present instance areconcerned with those which are obtained from intermediates whichrepresent hydroxylated esters of the sulfonic acid radical. For thisreason the introduction of an hydroxylated residue in the carboxylichydrogen position with subsequent sulfation does not yield compounds ofthe kind herein contemplated. If this type of sulfation takes placealong with the sulfation of an hydroxylated residue, present in thesulfomc hydrogen atom position, then there is no objection and suchsulfation is entirely immaterial. Thus, contemplating the sulfo fattyacids from the standpoint of the car- 'boxylic hydrogen atom, it isimmaterial whether this atom remains as such or is converted into or isreplaced by a hydroxylated hydrocarbon residue or changed into someother form such as an amido or salt form. As will be subsequentlypointed out, we prefer to replace the carboxylic hydrogen atom'by analkyl, aralkyl, or alicyclic radical.

If the sulfonic acid is converted into the sodium salt withoutneutralization of the carboxylic hydrogen atom, and if such monobasicsalt is reacted with glycol chlorhydrin so as to eliminate sodiumchloride, one has available an hydroxylated ester of the kind desired,in which the carboxylated hydrogen remains as such. Such material may besulfated without change in regard to the carboxyl group. The finalproduct may be neutralized so that the carboxylic hydrogen atom may bereplaced by any of the various metals or groups which are suitable forreplacing'the sulphato hydrogen atom. I It is also'to be noted that ifthe fatty acid present contains a hydroxy group, as in the case of-ricinoleic acid, hydroxy stearic acid, orthe like, 'or if it containsan ethylene linkage such as oleic acid, then sulfation at such reactivepositions may take place along with sulfation of the hydroxylatedhydrocarbon radical which has replaced the sulfonic hydrogen atom.Needless to say, such acidic hydrogen atom can be replaced by anysuitable metal or the like in the same manner as indiacids into thesulfonchloride, and subsequently,

reacting the sulfonchloride with the polyhydric alcohol with theliberation of hydrochloric acid.

' Another procedure involves reaction between the cated in connectionwith the sulfate radical-intro- 7 5 tioned Hoefielmann patent.

sulfonic acid, or preferably, a salt, such as the sodium salt, and achlorohydrin.

The preferred way of preparing such materials is to use the proceduredescribed in U. ,8. Patent No. 2,208,581, dated July 23, 1940, toHoefielmann. Briefly stated, the procedure employed is to obtain a freesulfonic acid in an anhydrous state and treat with a compound containingan ethylene oxide radical. As typical examples of applicable compoundsmay be mentioned glycerine epichlorhydrin, glycide alcohol, ethyleneoxide, propylene oxide, butene-Z-oxide, butene-l-oxide, isobutyleneoxide, butadiene oxide, butadiene dioxide, chloroprene oxide, isopreneoxide, decene oxide, styrene oxide, cyclohexylene oxide, cyclopenteneoxide, etc.

Note, however, that there are certain differences between the procedureemployed for the manufacture of the intermediate raw material and theprocedure as employed in said aforemen- The Hoeifelmann methodcontemplates treatment of sulfonic acids which are not necessarilysurface-active, for instance, benzene-sulfonic acid, with an olefineoxide, so as to produce materials which, for the main part, arewater-soluble and surface-active.

Ithappens that invariably the esters of the high molal sulfonic. acidsare insoluble in absence of a recurring ether linkage. In order toobtain compounds of the kind herein contemplated, one must stoptreatment with the olefine oxide, i. e., oxyalkylation, before watersolubility is obtained; and furthermore, it is desirable to stop watersolubility at the earliest stage. In other words, the. olefine oxideemployed, whether ethylene oxide, propylene oxide, butylene oxide,glycidol, methyl glycidol, or the like, is a comparatively expensivereagent; and one is only concerned with obtaining a reactive hydroxylradical for a subsequent sulfation step. There is no objection to thepresence of a recurring ether linkage, provided that the ester is stillwater-insoluble. This may be illustrated in the following manner, usingethylene oxide as the reactant.

But materials illustrated by any of the three subsequent types:

are just satisfactory,provided that the ester,

prior to sulfation, is water-insoluble. In some instances the presenceof the recurring ether in obtaining a malinkage may give some addeddesirable characteristic. Ordinarily speaking, one is concerned onlywith minimum reactant cost; and thus, the use of an excess amount of theolefine oxide is not justified. One is not attempting to obtain watersolubility by means of the expensive oxyalkylation step. As has beenemphasized, the ester obtained must be water-insoluble, regardless ofhow much or how little alkylene oxide is employed. Generally speaking,40 moles of alkylene oxide per mole of sulfonic acid may be consideredas an upper limit, but obviously, solubility is influenced by thealkylene oxide employed. Butylene oxide naturally will not cause asulfonic acid to be converted into a water-solubleester as readily asethylene oxide.

Thus, having obtained hydroxylated water-insoluble esters-and they maybe polyhydroxylated and may or may not contain the recurring etherlinkagethe next step is to submit them to a conventional sulfationprocess. The sulfation of such materials is the conventional procedureemployed for the sulfation of fatty acids or fats containing th hydroxylradical or ethylene linkage, such as oleic acid, olein, ricinoleic acid,triricinolein, monostearin, and the like. A similar procedure isemployed in the sulfation of amides derived from fatty acids andhydroxylated amines, such as the stearic acid amide of monoethanolamine.A similar procedure is employed in connection with the sulfation of highmolal alcohols and other similar materials.

Briefly stated, the procedure consists in treating the material with theamount of sulfating agent at least molecularly equal to the material tobe sulfated; and usually, the sulfating agent is employed inconsiderable excess, for instance, from 50% excess to 200% excess, basedon molal proportions. sulfating agents include sulfuric acid ofcommerce, monohydrate, oleum of various strengths, chlorosulfonic acid,sulfamic acid, etc. Sulfonation is generally conducted at a relativelylow temperature, from approximately zero degrees centigrade to atemperature of -40 C. or therabouts. sulfation can be conducted in thepresence of a solvent, such as liquid sulfur dioxide, chlorlnatedhydrocarbons, dioxane, ethyl ether, propyl ether, etc. Sometimes it isdesirable to add materials which tend to take up any water which may beformed, such as organic anhydrides, including acetic anhydride. Whensulfation is complete, which is usually indicated by absolutely clearsolubility of the sulfated product, it is generally washed immediatelyso as to remove the excess sulfating agent. Washing is generallyconducted wi h cold water, chilled brine, or ice. The sulfated materialis permitted to separate and the dilute draw-01f acid withdrawn. Thesulfated mass may be employed as such, or may be neutralized in anyconvenient manner with any one of the conventional basic materialsfrequently employed, such as caustic soda, caustic potash, ammonia,various hydroxylated amines, including monoethanolamine, diethanolamine,triethanolamine: and non-hydroxylated amines, including amylamine,benzylamine, cyclohexylamine, and the like. Such materials may beneutralized with polyvalent compounds, such as calcium oxide, magnesiumoxide, polyamines, including ethylene diamine, diethylene triamine,triethylene tetramine, etc.

Example 1 The sulfonic acid derivative of stearic acid is producedaccording to Example 1 of aforementioned Gunther and Hetzer Patent No.1,926,442. The sulfo stearic acid so obtained is converted into theanhydrous state by any suitable procedure. It may be heated toapproximately to C., and dried carbon dioxide gas passed through untilthe material is anhydrous. It may be dried in a vacuum drier so as toyield an anhydrous material. It may be distilled in presence of aninsoluble solid, such as xylene, so that the xylene is permitted tocarry ofi water during the distillation. Vapors, so obtained, arecondensed and the water separated from the xylene. The xylene can bereturned for re-circulation, so as to carry off more water.

Having obtained a non hydrous material of the kind. above described, itis diluted with several times its weight of anhydrous ethyl alcohol andrefluxed until the carboxyl hydrogen atom has been replaced by an ethylradical. One pound mole of the anhydrous ethyl stearate sulfonic acid,so obtained, is treated with one to three moles of ethylene oxide in themanner described in the aforementioned Hoeifelmann Patent No. 2,208,581,so as to yield a water-insoluble ester. Such ester is sulfated in theconventional manner employed for such type material with approximately65% to 100% by weight of monohydrate, The sulfation is most convenientlyconducted in apparatus designed to mix even solid materials with thesulfating agent. A sulfation temperature of approximately 35-45 C. isemployed. The acid is added as rapidly as possible, and as a rulesulfation can be completed within 2-4 hours. When sulfation is complete,the acid mass should give an absolutely clear, limpid, solution inwater. Failure to obtain such clearly soluble sulfated mass is due toeither over-sulfation or undersulfation. Over-sulfation means that theperiod of sulfation is too long and decomposition of the sulfatedmaterial took place progressively with sulfation. In such case, it isprobable that the period of sulfation should be decreased somewhat.Under-sulfation can be corrected by increasing the volume of sulfatingagent or increasing its activity, for instance, using a mixture of oleumand monohydrate, or else perhaps, extending the period of sulfationslightly. As is understood by those skilled in the art, such sulfationprocedure depends on the particular sulfating agent employed, and thereis no difliculty in varying these factors so as to obtain absolutelywatersoluble properties. When sulfation is complete, the mass is washedwith cold water, or preferably, with a mixture of chipped ice and Water.The amount of water added is preferably equal to the amount of sulfatingagent added. The mixture is stirred and allowed to stand the minimumlength of time necessary to give a complete separation. Sometimesseparation is hastened by the use of a chilled brine instead of water,or by the addition of a solvent, particularly if such solvent is notobjectionable in the final product. Such solvent may be a material ofthe kind exemplified by xylene, kerosene, propyl ether, and the like.After separation is complete, the waste acid is withdrawn and the acidmass neutralized in any convenient manner. Generally speaking, it is ourpreference to neutralize with ammonia to slightly past the methyl orangeendpoint, i. e., until the material shows just the slightest basicity.The product so obtained may be employed for various purposesQandparticularly for demulsification.

Example 2 The palmitic acid derivative, as described in Example 2 in theaforementioned U. S. Patent No. 1,926,442 is used in place of thestearic-acid derivative employed in Example 1 in the present instance.

Example 3 The oleic acid derivative described in Example 4 of theaforementioned Patent No. 1,926,442 is employed instead of thecorresponding stearic acid derivative described in Example 1 in thpresent instance.

Example 4 A sulfo-oleic acid is manufactured in themanner described inExample 4 of aforementioned U. S. Patent No. 1,931,491 and substitutedin place of the corresponding stearic acid derivative in Example 1 ofthe present instance.

Example 5 Alpha-sulfa lauric acid is obtained in the manner described inthe aforementioned U. S. Patent No. 1,910,459 and employed instead ofthe corresponding stearic acid derivative in Example 1 of the presentinstance.

Example 6 Example 7 The same procedure is followed as in Examples 1-6,inclusive, preceding, except that four to six moles of ethylene oxideare used instead of one to three.

Example 8 Propylene or butylene oxide is substituted for ethylene oxidein Examples 1-7, inclusive, preceding.

Example 9 The same procedure is followed as in Examples 1-8, inclusive,except that an amine of the kind exemplified by monoamylamine,cyclohexylamine, or benzylamine is used as a neutralizing agent.

It is to be noted that the last example illustrates a type in which thecompounds obtained are water-insoluble. Such water-insoluble types areparticularly adaptable for many purposes, and in fact, in many instancesare just as. desirable, or even more desirable for demulsification ofcertain crude oils than are the corresponding water-soluble types. I Inthe sulfation step it has been previously pointed out that a solvent maybe employed, particularly if the material employed is substantiallysolid at the sulfation temperature. A class of very suitable solventsincludes the chlorinated alkanes, such as chloroform, carbontetrachloride, trichlorethylene, di-

chlorpentane, etc. Incidentally, in some in- I stances, particularlywhere glycidol is used for oxy-alkylation, one may obtain an ester inwhich more than one acid sulfate radical is introduced. Conventionaldemulsifying agents employed in such, or after dilution with anysuitable solvent,

"such as water; petroleum hydrocarbons, such as the treatment of oilfield emulsions are used as cresol, anthracene oil, etc. Alcohols,particularly aliphatic alcohols, such as methyl alcohol, ethyl alcohol,denatured alcohol, propyl alcohol, butyl alcohol, hexyl alcohol, octylalcohol, etc., may be employed as diluents. Miscellaneous solvents, suchas pine oil, carbon tetrachloride, sulfur dioxide extract obtained inthe refining of petroleum, etc., may be employed as diluents. Similarly,the material or materials herein described, may be admixed with one ormore of the solvents customarily used in connection with conventionaldemulsifying agents. Moreover, said material or materials may be usedalone, or in admixture with other suitable well known classes ofdemulsifying agents.

It is well known that conventional demulsifylng agents may be used in awater-soluble form, or in an oil-soluble form, or in a form exhibitingboth oil and water-solubility. Sometimes they may be used in a formwhich exhibits relatively limited oil solubility. However, since suchreagents are sometimes used in a ratio of 1 to 10,000, or 1 to 20,000,or even 1 to 30,000, such an apparent insolubility in oil and water isnot significant, because said reagents undoubtedly have solubilitywithin the concentration employed. This same fact is true in regard tothematerial or materials herein described.

We desire to point out that the superiority of the reagent ordemulsifying agent contemplated in our herein described process forbreaking petroleum emulsions, is based upon its ability to treat certainemulsions more advantageously and at a somewhat lower cost than ispossible with other available demulsifiers, or conventional mixturesthereof. It is believed that the particular demulsifying agent ortreating agent herein described will find comparatively limitedapplication, so far as the majority of oil field emulsions areconcerned; but we have found that such a demulsifyingagent hascommercial value, as it will economically break or resolve oil fieldemulsions in a number of cases which cannot be treated as easily or atso low a cost with the demulsifying agents heretofore available.

In practising our process, a treating agent or demulsifying agent of thekind above'described is brought into contact with or caused to act uponthe emulsion to be treated, in any of the various ways, or by any of thevarious apparatusnow generally. used to resolve orbreak petroleumemulsions with a chemical reagent, the above procedure being used eitheralone or in combination with other demulsifying procedure, such as theelectrical dehydration process.

The demulsifier herein contemplated may be employed in connectionwithwhat is commonly known as down-the-hole procedure, i. e., bringingthe demulsifier in contact with the fluids of the well at the bottom ofthe well, or. at some point prior to their emergence. This particulartype of application is decidedly feasible when the demulsifier is ,usedin connection with acidification of calcareous oil-bearing strata,especially if suspended in or dissolved in the acid employed foracidification.

In the hereto appended claims, the word acyl is used in referenceto theradical RSQz; i. e., one

can conveniently consider the sulfonic acid .RSOsH in terms of a formulaindicating part of also materials of the kind in which the carbon atomchain is interrupted at least once by an oxygen atom, as, for example,diethylene glycol, diglycerol, etc.

It may be well to emphasize that the compounds of the kind hereincontemplated may be manufactured by any suitable method; and it is notintended to limit the compounds to any particular method of manufacture.When manufactured by the use of an alkylene oxide, it is our preferenceto use ethylene oxide, propylene oxide, or butylene oxide.

It is to be noted that the sulfato sulfonates and the sulfato sulfonicacids referred to in the claims are surface-active in the same sensethat sulfonic acids themselves are surface-active. Furthermore, it is tobe noted that some sulfonic acids might be of the polysulfonic acidtype, i. e., as exemplified by disulfonic acids. There is no objectionto the use of such raw materials as reactants, and it is obvious thatsuch procedure presents a means by which one obtains an ester in whicheither one or both terminal hydroxyl radicals may be sulfated.

The oxidation of certain fractions derived from paraffin base crudesyields monocarboxy aliphatic acids which are isomers of thenaturally-occurring fatty acids of the saturated type, i. e.,corresponding to lauric acid or the like, with the difference thatinstead of having straight carbon atom chains, such acids are likely tohave various types of branched chains, and in some instances, thecarboxyl radical is not attached to an end carbon atom, but may beattached to an intermediate carbon atom. bviously, such compounds can beconverted into sulfonic acids in the same manner employed for theconversion of lauric acid, palmitic acid, stearic acid or the like, andsuch sulfo derivatives may be considered as the obvious functionalequivalent of materials of the type herein contemplated, and it isintended that they should be so considered in the hereto appendedclaims.

Once more attention is directed to the fact that in the hereto appendedclaims the reference to an acyl group is not to the acyl group derivedfrom the carboxyl radical, but to the acyl group derived from thesulfonic acid radical. Furthermore, it is understood that it isimmaterial what form the carboxyl radical takes, i. e., whether it ispresent in the form of the free acid, in the form of a salt, or in theform of the ester. All this has been indicated previously.

Having thus described our invention, what we claim as new and desire tosecure by Letters Patent is:

1. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsiflercomprising a sulfato sulfonate derived from a polyhydric alcohol inwhich one hydroxy hydrogen atom has been replaced by the acyl radical ofa higher fatty acid sulfonic acid; and another hydroxy hydrogen atom ofsaid polyhydric alcohol has been replaced by the linkage:

o t-o which in turn is united with a cation; said compound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that the hydroxylated ester derived byreplacing one hydroxy hydrogen atom of the aforementioned polyhydricalcohol by the aforementioned acyl radical is water-insoluble.

2. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsifiercomprising a water-soluble sulfato sulfonate derived from a polyhydricalcohol in which one hydroxy hydrogen atom has been replaced by the acylradical of a higher fatty acid sulfonic acid; and another hydroxyhydrogen atom of said polyhydric alcohol has been replaced by thelinkage:

which in turn is united with a cation; said come pound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that the hydroxylated ester derived byreplacing one hydroxy hydro gen atom of the aforementioned polyhydricalcohol by the aforementioned acyl radical is waterinsoluble.

3. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsifiercomprising a Water-soluble sulfato sulfonate derived from an aliphaticpolyhydric alcohol in which one hydroxy hydrogen atom has been replacedby the acyl radical of a higher fatty acid sulfonic acid; and anotherhydroxy hydrogen atom of said polyhydric alcohol has been replaced bythe linkage:

which in turn is united with a cation; said compound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that the hydroxylated ester derived byreplacing one hydroxy hydrogen atom of the aforementioned polyhydricalcohol by the aforementioned acyl radical is water-insoluble.

4. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsifiercomprising a neutral water-soluble sulfato sulfonate derived from analiphatic polyhydric alcohol in which one hydroxy hydrogen atom has beenreplaced by the acyl radical of a higher fatty acid sulfonic acid; andanother hydroxy hydrogen atom of said polyhydric alcohol has beenreplaced by the linkage:

which in turn is united with a cation; said compound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that the hydroxylated ester derived byreplacing one hydroxy hydrogen atom of the aforementioned polyhydricalcohol by the aforementioned acyl radical is water-insoluble.

5. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsifiercomprising a water-soluble sulfato sulfonate derived from an aliphaticpolyhydric alcohol in which one hydroxy hydrogen atom has been replacedby the acyl radical of a. higher fatty acid sulfonic acid; and anotherhydroxy hydrogen atom of said polyhydric alcohol has been replaced bythe linkage:

which in turn is united with a cation; said compound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that the hydroxylated ester derived byreplacing one hydroxy hydrogen atom of the aforementioned polyhydricalcohol by the aforementioned acyl radical is water-insoluble; saidaliphatic polyhydric alcohol being characterized by the fact that thehywhich in turn is united with a cation; said compound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that thehydroxylated ester'derived byreplacing onehydroxy hydrogen atom of the aforementioned polyhydricalcohol by the aforementioned acyl radical is water-insoluble; saidaliphatic polyhydric alcohol being characterized by the fact that the Ihydrocarbon radical present contains. at least two carbon atoms and notmore thantsix carbon rived from an unsaturated fatty acid. v

7. A'pr'ocess "for breaking petroleum-emulsions atoms; and said fattysulfonic acid being deof the water-in -oil type, characterizedby s'ubajecting the'emulsion to the action of a-dem'ul-r sifier comprising awater-soluble sulfato sulfonate derived from an aliphatic polyhydric alcohol in which one hydroxy hydrogen atom has been replaced by the acylradical of a higher fatty acid sulfonic acid; and another hydroxyhydrogen atom of said polyhydric alcohol has been replaced by thelinkage:

which in turn is united with a cation; said compound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that the hydroxylated ester derived byreplacing one hydroxy hydrogen atom of the aforementioned polyhydricalcohol by the aforementioned acyl radical is water-insoluble; saidaliphatic polyhydric alcohol being characterized by the fact that thehydrocarbon radical present contains at least two carbon atoms and notmore than six carbon atoms; and said fatty sulfonic acid being derivedfrom a saturated fatty acid.

8. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsifiercomprising a water-soluble sulfato sulfonate derived from an aliphaticpolyhydric alcohol in which one hydroxy hydrogen atom has been replacedby the acyl radical of a higher fatty acid sulfonic acid; and'anotherhydroxy hydrogen atom of said polyhydric alcohol has been replaced bythe linkage:

which in turn is united with a cation; said compound being furthercharacterized by the fact that the selected sulfonic acid and selectedpolyhydric alcohol must be such that the hydroxylated ester derived byreplacing one hydroxy hydrogen atom of the aforementioned polyhydricalcohol by the aforementionel acyl radical is water-insoluble; saidaliphatic polyhydric alcohol being characterized by the fact that thehydrocarbon radical present contains at least two carbon, atoms and notmore than six carbon atoms; and said fatty sulfonic acid being derivedfrom an hydrcxylated fatty acid.

MELVIN DE GROOTE. BERNHARD KEISER.

